Stabilized fluoroelastomer compositions

ABSTRACT

Vulcanizates of certain fluoroelastomer terpolymer compositions, wherein the terpolymer is derived from tetrafluoroethylene, perfluoro(methyl vinyl ether), and a cure-site monomer, and further wherein the composition contains non-black filler, exhibit significantly improved stability upon heat aging when small quantities of quinacridone-type pigments are incorporated therein.

TECHNICAL FIELD

This invention relates to certain vulcanizable fluoroelastomercompositions, wherein the fluoroelastomer is a terpolymer derived fromtetrafluoroethylene, perfluoromethyl perfluorovinyl ether and acute-site monomer, which terpolymers are vulcanizable to usefulelastomeric materials characterized by excellent physical properties andresistance to environmental attack. These materials can be fabricatedinto mechanical parts such as O-rings, flange seals, gasket stock, pumpdiaphragms and liners and are particularly useful where extraordinaryresistance to heat and corrosive fluids is required. In particular, thisinvention relates to improvements in stability of such compositionscontaining non-black fillers upon heat aging by incorporating thereinsmall quantities of quinacridone-type pigments.

BACKGROUND ART

Kalb et al., "Polymerization Reactions and New Polymers", Advances inChemistry Series, No. 129, 13-26 (1973) discloses certain copolymers oftetrafluoroethylene, perfluoro(methyl vinyl ether) and a third monomerselected from the group consisting of:

(a) perfluoro(4-cyanobutyl vinyl ether),

(b) perfluoro(4-carbomethoxybutyl vinyl ether),

(c) perfluoro(2-phenoxypropyl vinyl ether), and

(d) perfluoro(3-phenoxypropyl vinyl ether).

Kalb et al also discloses the outstanding solvent and chemicalresistance that can be obtained with these elastomers.

U.S. Pat. No. 3,546,186 granted Dec. 8, 1970 to Gladding and Sullivan,discloses certain vulcanizable copolymers of substituted perfluorovinylether. In particular, among the many and varied copolymers disclosed byGladding and Sullivan, there are disclosed terpolymers derived fromtetrafluoroethylene, perfluoromethyl perfluorovinyl ether and acure-site monomer which can be, among other things,perfluoro(4-cyanobutyl vinyl ether) or perfluoro(4-carbomethoxybutylvinyl ether).

U.S. Pat. No. 3,467,638, granted Sept. 16, 1969 to Pattison, disclosescertain vulcanizable copolymers of substituted perfluorovinyl ethers. Inparticular, among the many and varied copolymers disclosed by Pattison,there are disclosed terpolymers derived from tetrafluoroethylene,perfluoromethyl perfluorovinyl ether and a cure-site monomer which canbe, among other things, perfluoro(2-phenoxypropyl vinyl ether).

U.S. Pat. No. 3,682,872, granted Aug. 8, 1972 to Brizzolara and Quarles,discloses certain vulcanizable copolymers of substituted perfluorovinylethers. In particular, among the many and varied copolymers disclosed byBrizzolara and Quarles there are disclosed terpolymers derived fromtetrafluoroethylene, perfluoromethyl perfluorovinyl ether and, as acure-site monomer perfluoro(3-phenoxypropyl vinyl ether).

Copending U.S. patent application Ser. No. 83,751, filed Oct. 22, 1979by Breazeale, discloses certain vulcanizable copolymers oftetrafluoroethylene, perfluoromethyl perfluorovinyl ether, and acure-site monomer which can beperfluoro(8-cyano-5-methyl-3,6-dioxa-1-octene).

It is non-black filled fluoroelastomer compositions based on thepolymers disclosed in the background art summarized above which can beimproved by the incorporation therein of small quantities ofquinacridone-type pigments.

DISCLOSURE OF THE INVENTION

The present invention relates to certain vulcanizable fluoroelastomercompositions, wherein the fluoroelastomer is a terpolymer derived fromtetrafluoroethylene, perfluoromethyl perfluorovinyl ether and acure-site monomer, and further wherein said composition contains atleast one non-black filler, said compositions further containing a smallquantity of at least one quinacridone-type pigments. The fluoroelastomercompositions of the present invention possess surprisingly superiorstability upon heat aging as compared with prior similar compositionscontaining no quinacridone-type pigment.

The terpolymers used in the composition of the present invention aresubstantially as described by Kalb et al, Gladding and Sullivan,Pattison, Brizzolara and Quarles, and Breazeale in the references citedabove and generally comprise copolymerized units of about 53-79.8 molepercent of tetrafluoroethylene (TFE), about 20-45 mole percent ofperfluoromethyl perfluorovinyl ether (PMVE), and 0.2-2 mole percent of acure-site monomer selected from the group consisting of:

(a) perfluoro(4-cyanobutyl vinyl ether),

(b) perfluoro(4-carbomethoxybutyl vinyl ether),

(c) perfluoro(2-phenoxypropyl vinyl ether),

(d) perfluoro(3-phenoxypropyl vinyl ether), and

(e) perfluoro(8-cyano-5-methyl-3,6-dioxa-1-octene).

Such terpolymers can be prepared by the procedures taught in thereferences cited above, and to the extent necessary to enable one ofordinary skill in the art to prepare the compositions of the presentinvention, the subject matter of Kalb et al. "Polymerization Reactionsand New Polymers", Advances in Chemistry Series, No. 129, 13-26 (1973),U.S. Pat. No. 3,546,186; U.S. Pat. No. 3,467,638; U.S. Pat. No.3,682,872 and U.S. application Ser. No. 83,751 are hereby incorporatedby reference into the present application. Preferably the compositionsof the present invention are based upon terpolymers in which thecure-site monomer is perfluoro(2-phenoxypropyl vinyl ether), and mostpreferably, they are based on such terpolymers in which the proportionsof the monomers are about 65.4-73.6 mole percent TFE, 26-34 mole percentPMVE, and the remainder is perfluoro(2-phenoxypropyl vinyl ether). Itshould be understood that exact determination of the monomer proportionsis difficult and that the values given are estimates based on infraredspectra. Nevertheless, the values recited are believed reasonablyaccurate and precise.

As with conventional vulcanizable fluoroelastomer compositions, it isfrequently desirable to mix fillers, reinforcing agents, stabilizers,plasticizers, lubricants or processing aids with the elastomer prior tovulcanization. Although a common additive is carbon black, frequently itis desirable to use one or more non-black fillers, such as titaniumdioxide, zirconium dioxide, silica, clay and asbestos.

When the fluoroelastomer composition contains such as non-black filler,the stability upon heat aging can be significantly improved byincorporating therein a small quantity, 0.1-10 phr, preferably 0.5-6phr, and most preferably 1-3 phr, of at least one quinacridone-typepigment.

Quinacridone-type pigments are generally known (see, e.g., Kirk-OthmerEncyclopedia of Chemical Technology, vol. 15, pp. 581-2 (1968) and thefollowing U.S. Pat. Nos.: 3,160,510; 3,686,009; and 3,748,162) and arecommercially available. Such pigments may be quinacridone ##STR1##quinacridone quinone ##STR2## substituted (e.g., alkyl or halosubstituted) quinacridone, substituted quinacridone quinone, andmixtures and solid solutions of such substituted and unsubstitutedquinacridones and quinacridone quinones. For example, the followingquinacridone pigments have demonstrated the ability to improve thestability, upon heat aging, of non black filled fluoroelastomercompositions based on TFE/PMVE/P2PVE terpolymers:

Colour Index Orange-48, which is a solid solution of quinacridonequinone, quinacridone and dihydroquinacridone; Colour Index Violet-19(C.I. no. 46 500), which can be a gamma quinacridone or a betaquinacridone; Colour Index Red-206, which is a solid solution containingquinacridone; Colour Index Orange-49, which is a solid solutioncontaining quinacridone quinone and dihydroquinacridone; Monastral®transparent Red B pigment, which is a solid solution containingquinacridone; and Colour Index Red 202, which is a solid solutioncontaining dichloroquinacridone quinone.

Preferred pigments include Colour Index Orange-48, Colour Index Red-206,and Colour Index Orange-49. The most preferred fluoroelastomercomposition of the present invention is one based on a TFE/PMVE/P2PVEterpolymer in which the monomer mole ratio is approximately65.4-73.6/26-34/0.4-0.6 and which includes about 2-3 phr of Colour IndexRed-206 pigment.

The following examples illustrate the fluoroelastomer compositions ofthe present invention and demonstrate their improved stability, uponheat aging, as compared with similar compositions that do not containany quinacridone-type pigment. In each of the following examples,standard elastomer processing and testing procedures were employed.Compounds were milled on a standard two-roll rubber mill at 60° C. Slabswere sheeted off the mill at the desired thicknesses. O-ring preformswere cigar-rolled on the mills. Slabs (6"×6"×0.080" i.e.,15.2×15.2×0.203 cm), pellets (Yerzley type, ASTM 0945, 1/2"×3/4" i.e.,1.27×1.91 cm) and O-rings (1" ID×3/4" cross-sectional diameter i.e. 2.54cm ID×0.32 cm cross-sectional diameter) were press cured in theappropriate molds at 190° C. for 30 minutes. Parts were removed from themolds and post-cured for 2 or 5 days under nitrogen in an oven whosetemperature was programmed to rise from 25° C. initially to 288° C. forthe last 24 hours.

Post-cured parts were tested as follows: small dumbbells (31/2"×1/8"with 5/8" wide tabs i.e., 8.89×0.64 cm with 1.59 cm wide tabs) were diedout of the slabs and pulled on the Instron at room temperature at 10in./min. i.e., 25.4 cm/min. Readings for modulus at 100% elongation(M₁₀₀), tension at break (T_(B)), elongation at break (E_(B)), andpermanent set (PS) were taken in accordance with ASTM D-412. Pellets andO-rings were tested for compression set by ASTM D 395B (70 hours at 204°C.). Hardness was measured on a Shore A type durometer. Results are readon an arbitrary scale where O is soft and 100 is hard. Parts were heataged in an air oven for 2-4 days at 600° F. (316° C.) and then tested asabove.

EXAMPLES 1-4

These examples demonstrate the superior stability, upon heat aging, ofcompositions treated with a small quantity of various quinacridonepigments (Examples 2-4) as compared with an untreated composition(Example 1):

    ______________________________________                                        Fluoroelastomer Composition                                                                1           2       3     4                                      ______________________________________                                        Polymer.sup.1                                                                              100         100     100   100                                    18-Crown-6.sup.2                                                                           3           3       3     3                                      K.sub.2 AF.sup.3                                                                           4.5         4.5     4.5   4.5                                    TiO.sub.2    20          17      18    18                                     Pigment:                                                                      C.I. Orange-48           3                                                    C.I. Violet-19, gamma            2                                            C.I. Violet-19, beta                   2                                      ______________________________________                                        Physical Properties                                                           Stress/Strain                                                                              (Post Cure - 2 days)                                             Initial                                                                       M.sub.100, MPa                                                                             10.5        12.8    9.9   10.8                                   T.sub.B, MPa 15.8        16.7    14.1  13.3                                   E.sub.B, %   140         130     130   120                                    PS, %        4           7       6     4                                      Heat Aged    (2 days/316° C.)                                          M.sub.100, MPa                                                                             5.7         7.2     6.3   6.3                                    T.sub.B, MPa 11.5        14.7    14.5  11.4                                   E.sub.B, %   250         210     240   200                                    PS, %        15          11      14    10                                     Heat Aged    (4 days/316° C.)                                          M.sub.100, MPa                                                                             3.8         5.0     4.8   Not                                    T.sub.B, MPa 6.0         11.0    8.5                                          E.sub.B, %   360         290     300   Run                                    PS, %        34          19      21                                           Compression Set                                                                            (70 h/204° C.)                                            Pellets, %                                                                    Initial      27          28      30    24                                     Heat Aged 2 days                                                                           76          68      77    73                                     Heat Aged 4 days                                                                           92          72      89    --                                     O-Rings, %                                                                    Initial      67          71      74    76                                     Heat Aged 2 days                                                                           90          82      99    85                                     Heat Aged 4 days                                                                           100+        100+    100+  --                                     Hardness, Shore A                                                                          76          78      77    78                                     ______________________________________                                         .sup.1 Copolymer of tetrafluoroethylene (67.5 mole %), perfluoromethyl        perfluorovinyl ether (32 mole %), and perfluoro(2phenoxypropyl vinyl          ether) (0.5 mole %)                                                           .sup.2 1,4,7,10,13,16hexaoxacyclooctadecane                                   .sup.3 Dipotassium salt of hexafluoroisopropylidenebis(4hydroxybenzene)  

EXAMPLES 5-9

These examples demonstrate the superior stability, upon heat aging, ofcompositions treated with a small quantity of various quinacridonepigments (Examples 6-9) as compared with an untreated composition(Example 5):

    ______________________________________                                        Fluoroelastomer Composition                                                                5       6       7     8     9                                    ______________________________________                                        Polymer.sup.1                                                                              100     100     100   100   100                                  18-Crown-6.sup.2                                                                           3       3       3     3     3                                    K.sub.2 AF.sup.3                                                                           4.5     4.5     4.5   4.5   4.5                                  TiO.sub.2    20      17      17    17    18                                   Pigment:                                                                      C.I. Orange-48       3                                                        C.I. Red-206                 3                                                C.I. Orange-49                     3                                          Monastral® Trans- -parent Red B      3                                    ______________________________________                                        -               Physical Properties                                                  5         6       7       8     9                                      ______________________________________                                        Stress/Strain                                                                          (Post cure - 2 days)                                                 Initial                                                                       M.sub.100, MPa                                                                         9.5         9.6     8.9   9.4   8.0                                  T.sub.B, MPa                                                                           14.8        15.8    14.4  14.4  12.2                                 E.sub.B, %                                                                             160         150     150   130   140                                  PS, %    2           4       4     4     3                                    Heat Aged                                                                              (2 days/316° C.)                                              M.sub.100, MPa                                                                         5.0         5.3     5.9   5.8   3.5                                  T.sub.B, MPa                                                                           10.6        12.8    12.9  12.3  10.6                                 E.sub.B, %                                                                             240         220     210   200   230                                  PS, %    11          8       7     7     8                                    Heat Aged                                                                              (4 days/316° C.)                                              M.sub.100, MPA                                                                         3.3         3.9     4.4   4.0   3.9                                  T.sub.B, MPa                                                                           7.0         10.7    10.9  10.0  8.3                                  E.sub.B, %                                                                             360         310     290   310   300                                  PS, %    24          14      12    15    14                                   Compression                                                                   Set      (70 h/204° C.)                                                O-Rings, %                                                                    Initial  77          78      77    77    78                                   Heat aged                                                                     (2 days) 93          81      82    84    87                                   Heat aged                                                                     (4 days) 100+        95      93    100   100+                                 ______________________________________                                         .sup.1 Copolymer of tetrafluoroethylene (67.5 mole %), perfluoromethyl        perfluorovinyl ether (32 mole %), and perfluoro(2phenoxypropyl vinyl          ether) (10.5 mole %)                                                          .sup.2 1,4,7,13,16hexaoxacyclooctadecane                                      .sup.3 Dipotassium salt of hexafluoroisopropylidenebis(4hydroxybenzene)  

EXAMPLES 10-13

These examples demonstrate the superior stability, upon heat aging, ofcompositions treated with a small quantity of quinacridone pigments(Examples 11 and 13) as compared with untreated compositions (Examples10 and 12), wherein the cure-site monomer of the terpolymer in thefluoroelastomer composition is a cyano monomer.

    ______________________________________                                        Fluoroelastomer Composition                                                               10        11       12     13                                      ______________________________________                                        Polymer.sup.4                                                                             100       100      100    100                                     Tetraphenyltin                                                                            3         3        3      3                                       DCH--18-Crown-6.sup.5                                                                     --        --       1      1                                       TiO.sub.2   10        10       20     20                                      C.I. Red-206                                                                              --        3        --     3                                       ______________________________________                                        Physical Properties                                                                     10        11      12.sup.6 13.sup.6                                 ______________________________________                                        Stress/Strain                                                                             (Post Cure - 2 days)                                              Initial                                                                       M.sub.100, MPa                                                                            1.8         3.0     2.6    4.5                                    T.sub.B, MPa                                                                              6.8         11.8    9.8    14.1                                   E.sub.B, %  190         200     260    200                                    Heat Aged   (2 days/316° C.)                                                                       (3 days/316° C.)                           M.sub.100, MPa                                                                            1.3         1.7     2.3    2.3                                    T.sub.B, MPa                                                                              6.3         6.8     7.8    9.8                                    E.sub.B, %  300         260     310    300                                    Compression Set                                                                           (70 h/204° C.)                                             Pellets, %                                                                    Initial     47          39      --     --                                     Heat Aged 2 days                                                                          22          17      --     --                                     O-Rings, %                                                                    Initial     --          --      34     28                                     Heat Aged 3 days                                                                          --          --      38     23                                     ______________________________________                                         .sup.4 copolymer of tetrafluoroethylene (69.7 mole %), perfluoromethyl        perfluorovinyl ether (29.6 mole %), and                                       perfluoro(8cyano-5-methyl-3,6-dioxa-1-octene) (0.7 mole %)                    .sup.5 2,5,8,15,21hexaoxatricyclo[20.4.0.0.sup.9,14 ]hexacosane (i.e.,        dicyclohexyl18-crown-6)                                                       .sup.6 After post cure in nitrogen for 2 days, these samples were heated      for an additional day at 316° C. under nitrogen                   

EXAMPLES 14-15

These examples demonstrate the superior stability, upon heat aging, ofcompositions treated with a small quantity of various quinacridonepigments (Example 15) as compared with an untreated composition (Example14):

    ______________________________________                                        Fluoroelastomer Composition                                                               14          15                                                    ______________________________________                                        Polymer.sup.4                                                                             100         100                                                   Tetraphenyltin                                                                            3           3                                                     DC--18-Crown-6.sup.5                                                                      1           1                                                     SiO.sub.2   10          10                                                    C.I. Red-206                                                                              --          3                                                     ______________________________________                                        Physical Properties                                                                        14.sup.6  15.sup.6                                               ______________________________________                                        Stress/Strain  (Post Cure - 2 days)                                           Initial                                                                       M.sub.100, MPa 3.7         4.3                                                T.sub.B, MPa   10.0        15.1                                               E.sub.B, %     250         240                                                Heat Aged      (3 days/316° C.)                                        M.sub.100, MPa 2.5         2.7                                                T.sub.B, MPa   8.1         9.5                                                E.sub.B, %     340         350                                                Compression Set                                                                              (70 h/204° C.)                                          O-Rings, %                                                                    Initial        51          57                                                 Heat Aged 3 days                                                                             60          58                                                 ______________________________________                                         .sup.4 Copolymer of tetrafluoroethylene (69.7 mole %), perfluoromethyl        perfluorovinyl ether (29.6 mole %) and                                        perfluoro(8cyano-5-methyl-3,6-dioxa-isooctane) (0.7 mole %)                   .sup.5 2,5,8,15,18,21hexaoxatricyclo[20.4.0.0.sup.9,14 ]hexacosane (i.e.,     dicyclohexyl18-crown-6)                                                       .sup.6 after post cure in nitrogen for 2 days, these samples were heated      for an additional day at 316° C. under nitrogen                   

EXAMPLES 16-20

These examples demonstrate the beneficial effect of quinacridone pigmentover a range of pigment concentrations:

    ______________________________________                                        Fluoroelastomer Composition                                                             16      17       18     19     20                                   ______________________________________                                        Polymer.sup.1                                                                           100     100      100    100    100                                  K.sub.2 AF.sup.3                                                                        4.5     4.5      4.5    4.5    4.5                                  18-Crown-6.sup.2                                                                        3.0     3.0      3.0    3.0    3.0                                  TiO.sub.2 20      20       20     20     20                                   C.I. Red-206                                                                            0       0.5      1.5    3.0    6.0                                  ______________________________________                                        Physical Properties                                                                      16    17      18      19    20                                     ______________________________________                                        Stress/Strain                                                                              (Post Cure - 5 days)                                             Initial                                                                       M.sub.100, MPa                                                                             9.6     9.6     9.0   10.3  9.9                                  T.sub.B, MPa 13.1    12.6    14.7  14.7  15.9                                 E.sub.B, %   130     120     140   140   150                                  Heat Aged (2 days)                                                            M.sub.100, MPa                                                                             4.0     4.7     5.7   7.0   6.6                                  T.sub.B, MPa 9.1     10.5    11.6  11.7  11.3                                 E.sub.B, %   230     210     220   210   230                                  Heat Aged (4 days)                                                            M.sub.100, MPa                                                                             2.3     3.1     3.9   4.3   4.4                                  T.sub.B, MPa 3.0     6.2     7.2   7.4   6.8                                  E.sub.B, %   370     330     310   310   300                                  Compression Set                                                                            (70 h/204° C.)                                            Pellets, %                                                                    Initial      43      43      39    39    45                                   Heat Aged                                                                     (2 days)     83      76      74    76    79                                   Heat aged                                                                     (4 days)     77*     84      85    81    82                                   O-Rings, %                                                                    Initial      --      73      70    67    80                                   Heat Aged                                                                     (2 days)     97      93      91    94    93                                   Heat Aged                                                                     (4 days)     100+    100+    100+  100+  100+                                 ______________________________________                                         .sup.1 Copolymer of tetrafluroethylene(69.7 mole %), perfluoromethyl          perfluorovinyl ether (29.6 mole %), and                                       perfluoro(8cyano-5-methyl-3,6-dioxa-1-octene) (0.7 mole %)                    .sup.2 1,4,7,10,13,16hexacyclooctadecane                                      .sup.3 Dipotassium salt of hexafluoroisopropylidenebis(4hydroxybenzene)       *anomalous result                                                        

EXAMPLES 21-24

These examples demonstrate the beneficial effect of quinacridone pigmentin fluoroelastomer compositions containing a variety of non-blackfillers:

    ______________________________________                                        Fluoroelastomer Composition                                                                21       22       23     24                                      ______________________________________                                        Polymer.sup.1                                                                              100      100      100    100                                     K.sub.2 AF.sup.3                                                                           4.5      4.5      4.5    4.5                                     DCH--18-Crown-6.sup. 5                                                                     4.0      4.0      4.0    4.0                                     TiO.sub.2 (grade 1) R902                                                                   20       20       --     --                                      TiO.sub.2 (grade 2) R960                                                                   --       --       20     20                                      C.I. Red-206 --       3        --     3                                       ______________________________________                                        Physical Properties                                                                     21        22      23       24                                       ______________________________________                                        Stress/Strain                                                                             (Post Cure - 5 days)                                              Initial                                                                       M.sub.100, MPa                                                                            8.6         9.4     7.4    10.1                                   T.sub.B, MPa                                                                              12.5        12.6    10.8   13.1                                   E.sub.B, %  170         140     150    130                                    Heat Aged                                                                     (3 days)                                                                      M.sub.100, MPa                                                                            Not         5.0     2.7    4.6                                    T.sub.B, MPa                                                                              test-       7.0     1.9    7.6                                    E.sub.B, %  able        310     350    300                                    Compression Set                                                                           (70 h/204° C.)                                             Pellets, %                                                                    Initial     25          39      47     40                                     Heat Aged                                                                     (3 days)    n.t.        100     100+   80                                     O-Rings, %                                                                    Initial     77          73      70     70                                     Heat Aged                                                                     (3 days)    n.t.        73      100+   89                                     ______________________________________                                         .sup.1 Copolymer of tetrafluoroethylene (67.5 mole %), perfluoromethyl        perfluorovinyl ether (32 mole %), and perfluoro(2phenoxypropyl vinyl ethe     (0.5 mole %)                                                                  .sup.3 Dipotassium salt of hexafluoroisopropylidenebis(4hydroxybenzene)       .sup.5 2,5,8,15,18,21hexaoxatricyclo[20.4.0.0.sup.9,14 ]hexacosane       

EXAMPLES 25-30

These examples demonstrate the beneficial effect of quinacridone pigmentin fluoroelastomer compositions containing a variety of non-blackfillers:

    ______________________________________                                        Fluoroelastomer Composition                                                               25      26     27    28   29    30                                ______________________________________                                        Polymer.sup.1                                                                             100     100    100   100  100   100                               K.sub.2 AF.sup.3                                                                          4.5     4.5    4.5   4.5  4.5   4.5                               DCH-18-Crown-6.sup.5                                                                      4.0     4.0    4.0   4.0  4.0   4.0                               SiO.sub.2   10      10     --    --   --    --                                Talc        --      --     13    13   --    --                                Asbestos    --      --     --    --   11.5  11.5                              C.I. Red-206                                                                              --      3      --    3    --    3                                 ______________________________________                                        Physical Properties                                                                     25   26     27     28    29    30                                   ______________________________________                                        Stress/Strain                                                                             (Post Cure - 5 days)                                              Initial                                                                       M.sub.100, MPa                                                                            12.7   12.8   10.8 11.8  --    --                                 T.sub.B, MPa                                                                              13.7   13.0   12.5 13.6  13.1  14.1                               E.sub.B, %  110    100    120  120   90    90                                 Heat Aged                                                                     (2 days)                                                                      M.sub.100, MPa                                                                            6.5    9.0    5.6  8.5   7.6   9.9                                T.sub.B, MPa                                                                              10.5   12.3   7.7  10.5  6.1   10.0                               E.sub.B, %  240    170    300  200   240   160                                Compression Set                                                                           (70 h/204° C.)                                             Pellets, %                                                                    Initial     42     43     72   55    48    48                                 Heat Aged                                                                     (2 days)    69     65     85   68    94    70                                 O-Rings, %                                                                    Initial     64     57     73   70    72    69                                 Heat Aged                                                                     (2 days)    97     84     92   87    100+  100+                               ______________________________________                                         .sup.1 Copolymer of tetrafluoroethylene (67.5 mole %), perfluoromethyl        perfluorovinyl ether (32 mole %), and perfluoro(2phenoxypropyl vinyl          ether) (0.5 mole %)                                                           .sup.3 Dipotassium salt of hexafluoroisopropylidenebis(4hydroxybenzene)       .sup.5 2,5,8,15,18,21hexaoxatricyclo[20.4.0.0.sup.9,14 ]hexacosane       

EXAMPLES 31-34

These examples demonstrate the beneficial effect of quinacridone pigmentin fluoroelastomer compositions containing a variety of non-blackfillers:

    ______________________________________                                        Fluoroelastomer Composition                                                                31       32       33     34                                      ______________________________________                                        Polymer.sup.1                                                                              100      100      100    100                                     K.sub.2 AF.sup.3                                                                           4.5      4.5      3.0    3.0                                     DCH--18-Crown-6.sup.5                                                                      4.0      4.0      --     --                                      18-Crown-6.sup.2                                                                           --       --       3.0    3.0                                     Hydrated alumina                                                                           11.2     11.2     --     --                                      ZrO.sub.2    --       --       26     26                                      C.I. Red-206 --       5        --     2                                       ______________________________________                                        Physical Properties                                                                      31     32       33       34                                        ______________________________________                                        Stress/Strain                                                                              (Post Cure - 2 days)                                             Initial                                                                       M.sub.100, MPa                                                                             7.3      9.2      6.5    7.7                                     T.sub.B, MPa 11.3     13.2     12.3   15.7                                    E.sub.B, %   140      160      170    180                                     Heat Aged (2 days)                                                            M.sub.100, MPa                                                                             2.4      4.5      3.2    4.8                                     T.sub.B, MPa 5.5      8.2      7.7    15.1                                    E.sub.B, %   400      290      330    280                                     Heat Aged (4 days)                                                            M.sub.100, MPa                                                                             --       --       Not    3.3                                     T.sub.B, MPa --       --       Test-  8.0                                     E.sub.B, %                     able   390                                     Compression Set                                                                            (70 h/204° C.)                                            Pellets, %                                                                    Initial      39       56       41     36                                      Heat Aged                                                                     (2 days)     --       --       n.t.   n.t.                                    Heat Aged                                                                     (4 days)     --       --       n.t.   n.t.                                    O-Rings, %                                                                    Initial      n.t.     62       62     56                                      Heat Aged                                                                     (2 days)     --       --       100+   76                                      Heat Aged                                                                     (4 days)     --       --       n.t.   n.t.                                    ______________________________________                                         .sup.1 Copolymer of tetrafluoroethylene (67.5 mole %), perfluoromethyl        perfluorovinyl ether (32 mole %), and perfluoro(2phenoxypropyl vinyl          ether) (0.5 mole %)                                                           .sup.2 1,4,7,10,13,16hexacyclooctadecane                                      .sup.3 Dipotassium salt of hexafluoroisopropylenebis(4hydroxybenzene)         .sup.5 2,5,8,15,18,21hexaoxatricyclo[20.4.0.0.sup.9,14 ]hexacosane       

EXAMPLES 35-36

These examples demonstrate the superior stability, upon heat aging, ofcompositions treated with a small quantity of quinacridone pigment(Example 36) as compared with untreated compositions (Example 35),wherein the monomer concentrations differ from that exemplified above.

    ______________________________________                                        Fluoroelastomer Composition                                                                 35      36                                                      ______________________________________                                        Polymer.sup.7 100     100                                                     K.sub.2 AF.sup.3                                                                            4.5     4.5                                                     18-Crown-6.sup.2                                                                            4.0     4.0                                                     TiO.sub.2     20      20                                                      C.I. Red-202  0       4.0                                                     ______________________________________                                        Physical Properties                                                                                     35         36                                       ______________________________________                                        Stress/Strain                                                                             (Post Cure - 5 days)                                              Initial                                                                       M.sub.100, MPa            11.6       13.5                                     T.sub.B, MPa              17.2       16.6                                     E.sub.B, %                150        130                                      Heat Aged (2 days)                                                            M.sub.100, MPa            5.9        6.8                                      T.sub.B, MPa              9.2        10.3                                     E.sub.B, %                330        280                                      Heat Aged (4 days)                                                            M.sub.100, MPa            Not        5.2                                      T.sub.B, MPa              Test-      4.0                                      E.sub.B, %                able       340                                      Compression Set                                                                           (70 h/204° C.)                                             Pellets, %                                                                    Initial                   40         44                                       Heat Aged (4 days)        100+       96                                       O-Rings, %                                                                    Initial                   79         77                                       Heat Aged (4 days)        Not Testable                                                                             100+                                     ______________________________________                                         .sup.2 1,4,7,10,13,16hexacyclooctadecane                                      .sup.3 Dipotassium salt of hexafluoroisopropylidenebis(4hydroxybenzene)       .sup.7 Copolymer of tetrafluoroethylene (71.5 mole %), perfluoromethyl        perfluorovinyl ether (28 mole %), and perfluoro(2phenoxypropylvinylether)     (0.5 mole %)                                                             

EXAMPLES 37-41

These examples demonstrate the superior stability, upon heat aging, ofcompositions treated with a small quantity of quinacridone pigment(Example 38) as compared with compositions treated with other typepigments (Examples 39-41), as well as with untreated compositions(Example 37):

    ______________________________________                                        Fluoroelastomer Composition                                                               37      38      39    40     41                                   ______________________________________                                        Polymer.sup.1                                                                             100     100     100   100    100                                  18-Crown-6.sup.2                                                                          3       3       3     3      3                                    K.sub.2 AF.sup.3                                                                          4.5     4.5     4.5   4.5    4.5                                  TiO.sub.2   20      17      18    18     18                                   C.I. Orange-48                                                                            --      3       --    --     --                                   C.I. Green-75                                                                             --      --      2     --     --                                   C.I. Blue-15.sup.5                                                                        --      --      --    2      --                                   Black SAF.sup.6                                                                           --      --      --    --     2                                    ______________________________________                                        Physical Properties                                                                     37    38      39      40     41                                     ______________________________________                                        Stress/Strain                                                                             (Post Cure - 2 days)                                              Initial                                                                       M.sub.100, MPa                                                                            10.5    12.8    9.8   10.2   11.2                                 T.sub.B, MPa                                                                              15.8    16.7    15.5  13.2   15.4                                 E.sub.B, %  140     130     140   120    130                                  PS, %       4       7       5     3      3                                    Heat Aged                                                                     (2 days)                                                                      M.sub.100, MPa                                                                            5.7     7.2     Not   Not    5.0                                  T.sub.B, MPa                                                                              11.5    14.7                 8.1                                  E.sub.B, %  250     210     test- test-  280                                  PS, %       15      11      able  able   17                                   Heat Aged                                                                     (4 days)                                                                      M.sub.100, MPa                                                                            3.8     5.0     Not   Not    Not                                  T.sub.B, MPa                                                                              6.0     11.0                                                      E.sub.B, %  360     290     Run   Run    Run                                  PS, %       34      19                                                        Compression Set                                                                           (70 h/204° C.)                                             Pellets, %                                                                    Initial     27      28      30    27     24                                   Heat Aged                   De-   Surface                                     (2 days)    76      68      graded                                                                              Melted 75                                   Heat Aged                                                                     (4 days)    92      72      89                                                O-Rings, %                                                                    Initial     67      71      78    75     77                                   Heat Aged                                                                     (2 days)    90      82      Melted                                                                              Melted 100                                  Heat Aged                                                                     (4 days)    100+    100+    --    --     --                                   Hardness, Shore A                                                                         76      78      75    78     79                                   ______________________________________                                         .sup.1 Copolymer of tetrafluoroethylene (67.5 mole %), perfluoromethyl        perfluorovinyl ether (32 mole %), and perfluoro(2phenoxypropyl vinyl ethe     (0.5 mole %)                                                                  .sup.2 1,4,7,10,13,16hexaoxacyclooctadecane                                   .sup.3 Dipotassium of hexafluoroisopropylidenebis(4hydroxybenzene)            .sup.5 Copper phthalocyanine pigment                                          Carbon black                                                             

INDUSTRIAL APPLICABILITY

The fluoroelastomer compositions of the present invention are useful inthe manufacture of finished parts such as O-rings, flange seals, gasketstock, pump diaphragms and liners. The extraordinary physical propertiesand resistance to environmental attack of such parts made from thesecompositions make them particularly well suited for applications inprocess streams subject to severe fluid service at inline temperaturesas high as 700° F. (371° C.) or in streams carrying highly corrosivefluids, such as hydrogen sulfide.

BEST MODE

Although the best mode of the present invention, i.e., the single bestfluoroelastomer composition of the present invention, will depend uponthe particular desired end use and the specific requisite combination ofproperties for that use, the single most preferred composition of thepresent invention is that described in detail in Example 24.

I claim:
 1. A vulcanizable composition comprising a fluoroelastomerwhich is a terpolymer derived from tetrafluoroethylene, perfluoromethylperfluorovinyl ether and a cure-site monomer, at least one non-blackfiller, and a small quantity of at least one quinacridone-type pigmentselected from the group consisting of quinacridone, quinacridonequinone, substituted quinacridone, substituted quinacridone quinone, andmixtures and solid solutions of such substituted and unsubstitutedquinacridones and quinacridone quinones.
 2. A composition of claim 1wherein the cure-site monomer is selected from the group consistingof:(a) perfluoro(4-cyanobutyl vinyl ether), (b)perfluoro(4-carbomethoxybutyl vinyl ether), (c)perfluoro(2-phenoxypropyl vinyl ether), (d) perfluoro(3-phenoxypropylvinyl ether), and (e) perfluoro(8-cyano-5-methyl-3,6-dioxa-1-octene). 3.A composition of claim 1 wherein the terpolymer consists essentially of53-79.8 mole percent of tetrafluoroethylene, 20-45 mole percent ofperfluoromethyl perfluorovinyl ether and 0.2-2 mole percent of thecure-site monomer.
 4. A composition of claim 2 wherein the terpolymerconsists essentially of 53-79.8 mole percent of tetrafluoroethylene,20-45 mole percent of perfluoromethyl perfluorovinyl ether and 0.2-2mole percent of the cure-site monomer.
 5. A composition of claim 2wherein the cure-site monomer is perfluoro(2-phenoxypropyl vinyl ether).6. A composition of claim 5 wherein the terpolymer consists essentiallyof 65.4-73.6 mole percent of tetrafluoroethylene, 26-34 mole percent ofperfluoromethyl perfluorovinyl ether and 0.5 mole percent ofperfluoro(2-phenoxypropyl vinyl ether).
 7. A composition of claim 1wherein the non-black filler is selected from the group consisting oftitanium dioxide, zirconium dioxide, silica, clay asbestos and hydratedaluminum oxide.
 8. A composition of claim 7 wherein the non-black filleris titanium dioxide.
 9. A composition of claim 1 wherein thequinacridone-type pigment is selected from the group consisting ofquinacridone, quinacridone quinone, substituted quinacridone,substituted quinacridone quinone, and mixtures and solid solutionsthereof.
 10. A composition of claim 9 wherein the quinacridone-typepigment is a solid solution containing quinacridone.
 11. A compositionof claim 1 wherein quinacridone-type pigment is present in thecomposition in an amount of 0.1-10 phr.